How many people are going to get to see "Tread" in a theater with an audience? Probably not many, but the reaction is an interesting phenomenon to watch, as people who had spent the previous hour growing more horrified by the paranoia and rage that lead to a rampage find themselves laughing or showing a tight sort of grin as the film hits its climax and the aggrieved subject starts going to town with a customized bulldozer. Are we just wired to respond to people taking creative action, the audacious absurdity overriding how toxic it actually is? For better or worse, that impulse makes this movie something that's hard to look away from.

It tells the story of Marvin Heemeyer, who settled near Granby, Colorado in the 1990s, made a fair number of friends (as an avid snowmobiler and master welder, he became known for custom sled bumpers). He worked in nearby auto shops and eventually opened his own on a piece of land he'd bought at an FDIC foreclosure auction, which is when the problems started: One of the rival bidders had been a Granby local with a lot of friends on the town board, and Heemeyer soon found himself at loggerheads with the local government and "Good Ol' Boys Club". Then things got weird - he purchased a Komatsu D355A bulldozer to park on his property to intimidate the neighbors, eventually bringing it inside his shop, holing up there and welding steel plates and concrete to the vehicle until it was a behemoth that the police could do nothing to stop as he drove it through the property of those he felt had wronged him on 4 June 2004.

The film starts telling the story from Heemeyer's perspective, talking with his friends and a former girlfriend, highlighting his skills and successes, playing up the parts of his story that viewers will likely be able to identify with somewhat - feeling like an outsider, being subject to onerous regulations, that sort of thing. It's a narrative that people are familiar with, so even if they remember the incident from fifteen years ago, it's easy to sew that together with what they're seeing to tell a tale of the little guy striking back at the establishment. The film has plenty of Heemeyer's own words from tapes he recorded in early 2004, and it's initially folksy and easy to connect with.

Writer/director Paul Solet has spent much of his career making horror films, with Tread being his first venture into documentary filmmaking, and it serves him well: He is helped by some of his source material, of course; Heemeyer's recordings become increasingly unhinged as the film goes on. Solet and his editor Darrin Roberts do a fine job of shifting what material is included and how over the course of the film, but he also includes a fair amount of reconstruction footage, and that helps him shape the narrative more directly. It can seem a bit of a cheat, but over the course of the film Solet, is careful to indicate that these moments are subjective, pairing them with the tape to illustrate Heemeyer's version of events, playing without other sound or slightly in slow motion to give the impression of imperfect memory. By the time he's ready to get to the main event, the picture of Heemeyer has shifted, even if the audience still has some lingering attachment to how things started.

Then the bulldozer goes through its first wall, and those recreations serve a different purpose, allowing Solet and his team to show something that was all about action and motion even though actual video of the incident, especially at the start where not enough people knew something insane was happening to take out their camcorders. Solet doesn't entirely lean on recreations or contemporary video, often switching back to interview clips in order to provide context for just how much danger Heemeyer was putting the people of this town in, and perhaps to also bleed off some of how a viewer can become engrossed in a well-constructed action scene. There's a moment earlier on where an interviewee talks about one of the movies Heemeyer watched over and over while modifying his bulldozer and how its redemption-through-violence plot didn't make much sense, and Solet seems keenly aware that he could wind up doing the same thing even if he were not careful to highlight that the destruction was, ultimately, petty.

He mostly succeeds, even if there is a sort of thrill in watching Heemeyer smash things as the constabulary struggles to counter him. That hook at least gets the audience in a position to think about whether the combination of anger and determination necessary to get to that point is fortunately rare or far too common.